Marine vessel



June 3, 1969 R. LEOPOLD 3,447,502

MARINE VESSEL Filed July 14, 1967 Sheet of s mmimmm I NVEN TOR.

ffz/nw [50, 040 I mar. 2&4

R. LEOPOLD June 3, 1969 MARINE VESSEL Sheet-iofS Filed July 14. 1967 Q I INVENTOR. ifz/x f/v [mm June 3, 1969 v I Y R. LEOPOLD 44 I I flz/l f/s/ ZIZLVENTOR BY 0 040 ma a 477ozA/E June 3, 1969 R. LEOPOLD 3,447,502

MARINE VESSEL Filed July 14, 1967 Sheet 5 of e INVENTOR. [Em/5N 160 040 Mamie 2L1 Arron/5% June 3, 1969 Filed July 14, 1967 mmmlllll lu IIIIIHHHHIIIWH.

R. LEOPOLD MARINE VESSEL Sheet v of6 Mml uunlnlw v I NVE NTOR. Zia/aw [50, 040

when

- Apnea/:7

United States Patent 3,447,502 MARINE VESSEL Reuven Leopold, Beverly Hills, Calif., assignor to Litton Systems, Inc., Beverly Hills, Calif., a corporation of Maryland Filed July 14, 1967, Ser. No. 653,429 Int. Cl. B63b 1/40 U.S. Cl. 114-61 13 Claims ABSTRACT OF THE DISCLOSURE A marine vessel which consists of three major portions: an underwater hull portion, an above water hull portion and a connecting hull portion. The underwater portion is a buoyant member which supports the above water portion in the form of a deck platform on a pair of streamlined connecting hulls, which render in part a fraction of the total buoyancy. This configuration greatly reduces the wave-making resistance of the ship because the member which renders the major portion of buoyancy is submerged and the waterplane area of the hull is reduced to a minimum.

This invention relates to a mobile marine vessel of a unique configuration which combines the advantages of both a submarine and that of a conventional, generally V-shaped surface ship.

To keep up with the afliuent world, an increased need has developed to improve methods for movement of cargo and personnel rapidly and efiiciently over the oceans and seas. Traditionally, ocean going ships have a generally V-shaped hull, with a large waterplane area (area of hull at the waterline) and, correspondingly, a large resistance to movement through water because of the waves generated by the V-shaped hull.

Heretofore, some designers proposed, mainly for offshore drilling purposes, utilizing two cylindrical displacement vessels to support a large deck platform on a number of surface-piercing struts. Such a ship has a limitation for a high speed transport vessel because of the extremely large diameter of the displacement vessels and general lack of static stability due to insufficient waterplane area. Such large diameters will either cause the cylindrical displacement vessels to extend above the waters surface, thus increasing wave resistance, or necessitate the vessels to be at a depth such that the draft of the ship will prevent it from entering most commercial ports. In addition, when traveling at high speeds, due to loss of pressure on the bottom part of the cylinders, those structures will sink to greater depth, adding wetted surface, thus increasing resistance.

As with most engineering systems, a ship is normally a compromise of many factors. If the qualities and characteristics of complex engineering systems are abstracted and viewed as functions which can be modeled mathematically, strong cross coupling terms are found among the various subsystems. Naturally each one of these subsystems performs a task and is characterized by a number of variables. The ease of designing the total system is influenced by the strength of the cross coupling terms. Therefore, an ideal system is one where the cross coupling terms are the weakest because then each individual subsystem can be independently optimized with respect to its own variables Without having to degrade other subsystems. The marine vessel of the present invention is a result of such analysis. It is an optimum solution to a volume-limited, high speed displacement-type marine transport system wherein each of the subsystems have been optimally designed.

One of the main features of the improved marine vessel of the present invention is that it overcomes the biggest problem facing surface vessels, that is wave-making resistance. This is accomplished by lowering the underwater portion of the vessel as far under water as possible (without limiting the draft in terms of entrance to harbors) and elevating over the waters surface the above water portion as high as possible to avoid seakeeping problems associated with slamming and wetness while, at the same time, allowing no excessive heights which could be detrimental from a structural point of View.

Therefore, an object of the present invention is to provide an improved marine vessel which overcomes the speed barrier plaguing, conventional displacement-type surface ships and includes better space utilization resulting in a smaller ship for the same load-carrying capacity.

A further object of the present invention is to provide a marine vessel having a pair of submerged displacement members, each having a squashed cylindrical cross section and gentle form change in the fore and aft direction to reduce form drag and a pair of streamlined hull sections having a reduced waterplane area to reduce both the form drag and the wave-making resistance of the vessel.

Briefly, the principles of the present invention are illustrated in a marine vessel which has three major portions: at least one underwater hull portion, an above water hull portion and at least two intermediate connecting portions. The underwater portion is comprised of at least one elongated buoyant member having fore and aft tapered ends, the above water portion is comprised of a support hull structure adapted to carry cargo and personnel and the connecting hull portions is comprised of at least a pair of streamlined slender hulls, each affixed to the underwater portion and to the above water portion.

These and other objects and advantages of this invention will become apparent from the following description taken in accordance with the specifications and constructed in conjunction with the accompanying drawings throughout, which like reference characters indicate like parts and in which:

FIG. 1 is a perspective view of one embodiment of the improved marine vessel constructed in accordance with the principles of the present invention; and

FIG. 2 is a perspective view of the marine vessel of FIG. 1 looking towards the stern of the vessel.

FIG. 3 is a bottom view of the marine vessel of FIG. 1 with the superstructure omitted for clarity;

FIG. 4 is a side elevational view of the marine vessel of FIG. 3 with the addition of additional rudders shown on the underwater hull portion, at the bow section;

FIG. 5 is a transverse sectional view taken along the lines 5-5 in FIG. 4; and

FIG. 6 is a transverse sectional view, taken at the bow section, of a second embodiment of a marine vessel constructed according to the principles of the present invention; and

FIG. 7 is a transverse sectional view, taken at the bow section, of a third embodiment of a marine vessel con structed in accordance with the principles of the present invention showing a single underwater hull portion; and

FIG. 8 is a perspective view of a modification of the third embodiment, illustrated in FIG. 7, looking from the stern and showing the single underwater hull portion having twin pod-like ends along with an airfoil-like shaped trailing edge of the midpart of the underwater hull portion; and

FIG. 9 is a perspective view of a fourth embodiment of the improved marine vessel constructed in accordance with the principles of the present invention, showing each underwater hull portion having two separate connecting hull portions; and

FIG. 10 is a perspective view of a fifth embodiment of the improved marine vessel, looking towards the stern of the vessel, showing four separate connecting and underwater hull portions; and

FIG. 11 is a bottom view of the marine vessel of FIG. with the superstructure omitted for clarity; and

FIG. 12 is a side elevational view of a sixth embodiment of the improved marine vessel with the superstructure omitted \for clarity, showing that the vessel may have more than four connecting and underwater portions and that the underwater hulls can have an airfoil shape; and

FIG. 13 is a transverse sectional view of a seventh embodiment of the improved marine vessel, with the superstructure omitted for clarity, showing that the underwater hull portion may have a shape other than elliptical.

Referring now to FIGS. l-4, the improved marine vessel of the present invention comprises an above water hull portion 10, an underwater hull portion 12 and a connecting hull portion 14. The above water portion 10 may 'be generally of practically any shape. Shown in FIG. 1, the above Water hull portion is configured with a generally flat upper surface for carrying and launching aircraft and has a substantially rectangular shape with a tapered bow section 11 and a substantially perpendicular stern section 13. As discussed in great detail later, since the above water portion 10 does not engage the water, it does not have a conventional V-shaped configuration; however, as shown in FIG. 5, it may have a slightly tapered bottom surface 16. This tapered surface 16 is introduced for seakeeping purposes specifically to divert water waves reaching the bottom part of the above Water portion of the hull. An above water hull portion 10, shaped as an aircraft carrier, has been shown for exemplary purposes only since the principles of the present invention can be applied to passenger and cargo vessels and to other marine vessel types "as well without varying from the scope of the invention.

The underwater portion 12 comprises one or more elongated buoyant displacement bodies or members 18 which, as shown in FIGS. 4 and 5, have elliptical or other squashed cylindrical shapes and have lengths substantially the same as that of the above water portion 10. If the buoyant members 18 are not substantially elliptical in shape, but rather cylindrical, they will have an increased vertical dimension resulting in an upper surface 20 being too close to the surface of the water or, in some cases, actually piercing the waters surface. Therefore, instead of achieving the reduction of wavemaking resistance, the problem becomes even more acute. While the above noted problem could be eliminated 'by submerging the buoyant members 18 to a greater depth, this would result in excessive draft of the vessel, thereby limiting its entrance to most commercial ports. The fore and aft ends of the buoyant members are tapered, thus reducing their form drap in Water. While not critical, it is desirable to have the buoyant members parallel and in the same horizontal plane.

The connecting hull portion 14, as shown in FIG. 4, is a pair of hull members 14 having a streamlined shape, such as concaving the outer surface into a parabolic shape. The hull members 14 are of a length greater than half the length of the buoyant members 18 but still not as great a the entire length of such members, thus permitting the fore and aft ends of the buoyant members 18 to extend beyond the ends of the connecting hulls 14. The connecting hulls 14 have a streamlined shape to reduce their surface-piercing area, thus in this fashion increasing the seakeeping qualities and seaworthiness of of the vessel. The hulls have a maximum width less than the maximum diameter of the elliptical buoyant members however, as shown in FIG. 6 in a second embodiment, the connecting hulls 14 need not be symmetrically positioned about the center line of the buoyant members 18 nor have streamlined surfaces of the same curvature. The eccentric location of the hulls 14 renders a higher stability measure with the same waterplane area. As desired, within the principles of this invention, the connecting hulls 14 may have surfaces of any number of streamlined shapes which may be curves of various configurations as shown in FIG. 6, or one or both surfaces substantially vertical, as shown in FIGS. 7 and 8.

conventionally, the ship would include at least one pair of rudders 24 which may be movably afiixed to the upper surfaces of the below water hull portion 12 near the aft end, and propellers 26 movably afiixed to the below water hull portion and operated by a power plant (not shown) to propel the ship through the Water. If desired, for increased and faster maneuverability, a second pair of rudders 24 may be provided near the forward end of the below water hull portion 12. This is shown in FIG. 4.

Since the large portion of the buoyancy is obtained well below the surface, this novel structure combines the quality of very low wave-making resistance with the very low form drag for the majority of the displacement. Therefore, for the submerged part of thi ship, the resistance is mostly due to frictional resistance. The streamlined surfaces of the connecting hulls also result in very small wave-making resistance and practically no form drag for connecting hulls, again mostly frictional resistance. This fact naturally results in low powering requirement and thus lower weight for the main power plant and the fuel for a specified endurance.

In addition, due to the very small waterplane area of the vessel, very good seakeeping qualities result and the parabolic distribution of the waterplane area between the top and bottom of the hulls results in good seaworthiness of the vessel.

In one specific embodiment of the adove discussed principles the buoyant members 18 have an elliptical cross section with a major axis of 32 feet, minor axis of 17 feet, and are 800 feet long. The buoyant members are connected to the deck structure by a single 700-foot long streamlined hull on each side, and optimum stiffened cylinders with parabolically bivariate struts. These dimensions were particularly chosen to increase stability by making an increase in waterplane area a function of heel and pitch angles. The struts are connected at the top by 800-foot longitudinal girders of box construction, ten feet sequare and reinforced. The deck transverse members are, in addition, connected to the vertical strut strength members by reinforced brackets. The cargo stowage deck structure is 40 feet high and 106 feet in beam with a length of 800 feet. The bow has a somewhat ship bow shape to avoid wetness and slamming and the bottom part of the box structure has a deadrise of five feet for seakeeping reasons.

Shown in FIGS. 7 and 8 is a third embodiment of the invention wherein the buoyant members rather than comprising a pair of elliptically-shaped bodies are a single rectangular buoyant body 30 substantially of the same width as the above water portion 10. The single underwater hull 30, as shown in FIG. 8, may have twin podlike ends 32 and a trailing edge 34 shaped like an airfoil on the portion of the hull between the pods 32. Each of the twin pods 32 functions to develop collect flow into the propeller race associated with the pod and the airfoilshaped trailing edge 34 increases the dynamic lift of the underwater hull, thereby reducing resistance. The rudders and propellers have been omitted from the embodiment for clarity; however, these elements would be located or shown in FIGS. 1 and 4.

The primary tradeoff which applies both to the single 7 and to the double buoyant member configurations i a tradeofr between wave-making resistance and frictional resistance. At high speeds, such as between 30 to 40 knots, the differential of Wave-making resistance is so large that even through the wetted surface of this improved vessel is larger than the wetted surface of a conventional ship of the same displacement, the total resistance will be less, thus overcoming a great barrier to increased speed of surface ships.

FIGS. 9l2 include additional embodiments of the principles of this invention. The below water hull portion and the connecting hull portion of all of these embodiments develop the reduced wave-making resistance and form drag that are characteristic of this invention. In the fourth embodiment, shown in FIG. 9, the connecting hull portion is shown comprising two separated segments 42, each aflixed to the same underwater hull portion 12. This configuration is desirable for long ships to decrease the wetted surface and thereby reduced resistance.

The fifth embodiments, FIGS. 10 and 11, divide each of the underwater hull portions into two separate bodies 50 and each of these bodies 50 supports a connecting hull portion 52. This configuration is particularly adaptable to long ships where the displacement does'not require an underwater hull portion of the same length as the above water hull portion.

FIG. 12 illustrates a sixth embodiment which divides the underwater and connecting hulls into more than two segments, shown as 60 and 62 respectively, and further illustrates the shaping of the underwater hull portions 60 into longitudinal airfoils such as those shaped like an aircraft wing. This configuration is desirable to gain increased dynamic lift, thereby reducing resistance.

FIG. 13 is a transverse sectional view of a seventh embodiment which has been included to illustrate that the underwater hull portions need not be elliptical but may have any squashed cylindrical shape. In this figure the underwater hull portion 70 includes one generally flat side and a curved upper surface. This shape has been included only by way of example, since within the principles of this invention the underwater hull portion may have many other shapes.

No structural or operational details have been included in the description of the present invention or shown in the figures since such details would be conventional in nature and would comprise such elements as plates, stifliers, flanges and other elements, and are not critical. Therefore for simplicity and clarity, the underwater, connecting and above water hull portions have been shown as solid members; however, it should be understood that these members would be constructed in a conventional fashion with standard elements and, if desired, would include chambers, passages and other details, together with the necessary personnel and equipment to make an operative ship. The below water portion 12 and connecting portion 14 have been described as being buoyant and typically would consist of one or more chambers or other devices to achieve buoyancy.

While a number of embodiments of this invention have been herein illustrated, it will be appreciated by those skilled in the art that other variations in the disclosed arrangements, both as to their details and as to the organization of such details may be made without departing from the spirit and scope hereof. Accordingly, it is intended that the foregoing disclosure and the showings made in the drawings shall be considered only as illustrative of the principles of this invention and not construed in a limiting sense.

What is claimed is:

1. A marine vessel consisting of:

a buoyant submerged underwater hull portion having a noncylindrical cross section;

an .above water hull portion in juxtaposition with said underwater hull portion; and

a connecting hull portion including a plurality of elongated hull members affixed to said underwater hull portion and to said above water hull portion for uniting said hull portions into a floatable marine vessel, said connecting hull portion having at least one concave side of a curvature defining the minimum horizontal cross-sectional area of said connecting hull portion to be substantially coincidental with the minimum water plane area of the connecting hull portion at predetermined operating speeds of said vessel wherein as said vessel is propelled through the water it developes less resistance at high speeds than a conventional ship having a substantially V- shaped hull.

2. The marine vessel of claim 1 wherein the underwater portion is a pair of totally submerged elongated, noncylindrically-shaped buoyant members, each aflixed to a different one of said elongated hull members.

3. The marine vessel of claim 2 wherein the buoyant members have elliptical shapes.

4. The marine vessel of claim 2 wherein the buoyant members are arranged in a horizontal plane and with their longitudinal axis extending parallel to each other.

5. The marine vessel of claim 1 wherein the connecting hull portion includes a pair of elongated streamlinedshaped hulls, each having concave sides.

6. The marine vessel of claim 5 wherein each of the two streamlined elongated connecting hull members have at least one surface shaped substantially like a segment of a parabola.

7. The marine vessel of claim 5 wherein said outer surfaces of each connecting hull member have different parabolic shapes and the longitudinal centerline of each of the hulls is not coaxial with the minor axis of a different one of the buoyant members.

8. The marine vessel of claim 1 wherein the buoyant submerged underwater portion is a rectangular-shaped buoyant body having the elongated connecting hull portions aflixed to the same major surface thereof.

9. The marine vessel of claim 8 wherein the rectangular-shaped buoyant body includes pod-like ends and a tapered trailing edge.

10. The marine vessel of claim 5 wherein each of the underwater portions includes a plurality of separate parts each individually coupled to the above water portion by said streamlined connecting hulls.

11. The marine vessel of claim 10 wherein each of the underwater portions is longitudinally shaped like an airfoil.

12. The marine vessel of claim 5 wherein each of the pair of streamlined hulls includes at least two separate parts, each affixed to the underwater hull portion and to the above water hull portion.

13. The marine vessel of claim 1 wherein vertical cross sections through the vessel at locations along the longitudinal axis of the vessel aft of the bow, at midships and forward of the stern, define segments of substantially similar areas.

References Cited UNITED STATES PATENTS 1,817,780 8/1931 Stack 11461 1,846,602 2/1932 Lake 114-665 1,861,338 5/1932 Faust 114-61 2,890,672 6/1959 Boericke 114-66.5 3,326,163 6/1967 Davis 11466.5 3,347,197 10/ 1967 Scherer 114-665 ANDREW H. FARRELL, Primary Examiner. 

